M-Enk在猫背根节切除后脊髓Ⅱ板层的表达  

M-Enk Expressing in the Lamina Ⅱ of Cat Spinal Cord after Deafferentation

作　　者：陈建军[1] 杨琴[1] 

机构地区：[1]成都医学院解剖学与组织胚胎学教研室,成都610083

出　　处：《四川大学学报（医学版）》2009年第6期1053-1055,共3页Journal of Sichuan University(Medical Sciences)

摘　　要：目的探讨猫脊髓背根神经节切除后,甲硫胺酸脑啡肽(M-Enk)在脊髓后角Ⅱ板层内的表达变化及M-Enk异类终末。方法10只成年雄性猫,在腹腔内注射麻醉下行腰1到骶2(L1～S2)单侧脊髓背根节切除术,建立猫背根节全切模型,术后分为急性组5只,存活2周,慢性组5只,存活2个月,观察到期后,动物心内灌注固定处死,取L6节段脊髓,采用免疫组化染色方法检测手术侧和对侧脊髓Ⅱ板层内M-Enk的表达,电镜下观察M-Enk异类终末。结果光镜下M-Enk阳性染色主要分布于脊髓Ⅱ板层的外侧份,成颗粒状和线条状,急性组手术侧与对侧非手术侧阳性染色无明显差异,慢性组两侧阳性染色均减弱,手术侧约强于对照侧。电镜下,在慢性组手术侧Ⅱ板层脊髓中,观察到简单终末,发现了M-Enk阳性非典型复合终末(ACT),它们较小,外观上呈圆形或椭圆形,多与两个突触后成分形成联系,突触活性带形较平直或向外凸,突触内含均匀清亮小泡或致密核心小泡。结论M-Enk在猫脊髓背根节切除后主要在脊髓Ⅱ板层外侧表达,M-Enk阳性ACT可能是脊髓背根节全切后的一种代偿终末。Objective To investigate the Methionine Enkephalin（M-Enk） expression in lamina Ⅱ of cat spinal cord and the atypical complex terminal（ACT） after complete dorsal rhizotomy.Methods 10 male adult cats were divided into 2 groups after carrying out the complete dorsal rhizotomy： acute group,which survived 2 weeks;chronic group,which survived 2 months.At maturity,all cats were perfused after anaesthesia,the L 6 segments of the spinal cord were removed and prepared for light and electron microscopy of M-Enk immunohistochemistry and for observing of ACT.Results M-Enk immuno-reactivity can be seen in laminal Ⅱ lateral sides both in operation and control sides in acute group.They were both decreased in chronic group on the photos by naked eyes,and little intensive in operation side on the photos.The immuno-positive ACTs have been founded in the Lamina Ⅱ of chronic operation side beside some M-Enk immunopositive simple terminals,they are round or ellipse in shape and usually form flat or convex two synapse with two post-compounds.ACTs contained both clear vesicles and dense core vesicles.Conclusion M-Enk express in operation side after complete dorsal rhizotomy is mainly on the lateral side in lamina Ⅱ.The M-Enk immuno-positive ACT may imply the mechanism of spinal cord plasticity.

关 键 词：脑啡肽(M-Enk) 脊髓可塑性 电镜免疫组化 猫 

分 类 号：R741[医药卫生—神经病学与精神病学]